1. Field
One or more embodiments described herein relate to a semiconductor device.
2. Description of the Related Art
The electrical characteristics of a semiconductor memory device tend to vary according to operating temperature. This is especially true various types of memory devices. In an attempt to improve operation of a volatile memory device, the refresh period may be shortened in an attempt to reduce leakage current, which may increase with temperature. Also, transistor control voltages may be changed because threshold voltage may increase with temperature.
Also, because the area of a semiconductor memory device may increase with increases in capacity, a difference in operating temperatures may occur with respect to location. In particular, when a semiconductor memory device and an application processor are mounted in a single package, differences in operating temperature may increase with respect to location, e.g., the distance between the semiconductor memory device and application processor at relatively high operating temperature.
Moreover, when a semiconductor memory device is controlled based on a representative temperature, problems may occur. For example, data may be lost in a region having an operating temperature higher than the representative temperature. Also, excessive power may be consumed due to frequent refresh operations or unnecessarily high control voltages in regions having operating temperatures lower than the representative temperature. Also, to install a plurality of temperatures sensors in the semiconductor memory device in an attempt to solve these problems is space inefficient.